The SNAP-PAC-EB2 brain is an I/O and communications processor for your control system. Designed primarily to work in distributed systems controlled by a SNAP PAC S-series or R-series controller, the SNAP-PAC-EB2 can also be used as intelligent remote I/O with Allen-Bradley industrial PLC systems. The SNAP-PAC-EB2 provides local intelligence that frees the controller (PAC or PLC) for supervisory tasks.

As an I/O processor, the SNAP PAC brain independently handles functions such as latching, thermocouple linearization, watchdog timers, and PID loop control. These functions continue to work on the brain even if communication with the SNAP PAC controller is lost.

The SNAP-PAC-EB2 brain supports all the SNAP I/O analog, digital, and serial input and output modules available on the Opto 22 website. These modules can all be mixed on the same mounting rack and placed in any position on the rack. The brain and modules mount on a SNAP PAC rack, which holds up to 4, 8, 12, or 16 modules.

NOTE: In order to use Opto 22 serial modules with an EB2 brain, the I/O should be controlled by a SNAP PAC controller running a PAC Control strategy.

In addition to I/O processing, the SNAP PAC brain communicates over a standard 10/100 Mbps Ethernet network. The brain is equipped with two switched Ethernet network interfaces. Because these interfaces share a single IP address and act just like an Ethernet switch, SNAP PAC brains can be installed in a multi-drop (daisy-chain) configuration, extending the control network without the added expense of additional Ethernet network hardware. SNAP PAC brains can also be installed in a star configuration using standard, off-the-shelf Ethernet network components.

The SNAP-PAC-EB2 brain supports communication using multiple protocols running simultaneously over Ethernet. Most customers use the PAC Project software suite for control, monitoring, and data acquisition. At the same time, you can communicate using other methods, including EtherNet/IP, Modbus/TCP, SNMP, SMTP, FTP, and OptoMMP. Communication with OPC 2.0-compliant clients is available through OptoOPCServer.

The SNAP-PAC-EB2 brain provides basic digital functions but does not offer high-speed digital functions; if you need high-speed counting (up to 20 KHz depending on the module), quadrature counting, pulse measurement, and frequency and period measurement, choose the SNAP-PAC-EB1 brain instead. For a complete list of features and specifications, see form #1689, the SNAP PAC Brains Data Sheet, under the Docs & Downloads tab.

NOTE: If you need a Factory Mutual-approved version of this brain, see the SNAP-PAC-EB2-FM.

Rechargeable
(recharges whenever the brain has power). 5-year life when power is off.
(Models manufactured before August 2007 have user-replaceable batteries.
See original user guide for details or contact Product Support.)

SNAP PAC brains are powerful and versatile I/O and network communications processors. Designed primarily to work in distributed systems controlled by a SNAP PAC controller, SNAP PAC Ethernet brains can also be used as intelligent remote I/O for Allen-Bradley Logix-based PLC systems.

SNAP PAC brains, one of the four components of the SNAP PAC System, provide I/O processing and network communications for your distributed SNAP PAC System. SNAP PAC Ethernet brains can also be used as intelligent remote I/O in an Allen-Bradley Logix-based PLC system.

This guide shows you how to install and use all SNAP PAC brains: wired Ethernet, Wired+Wireless, and serial.

This guide is a comprehensive introduction to the SNAP PAC System. The guide describes the system's four components (software, controllers, brains, and I/O); shows how to build a basic system and how to expand it; and includes installation instructions, wiring diagrams, dimensional drawings, and specifications for parts.

This document shows examples of system architecture for PC-based I/O control systems and lists Opto 22 products that work together for PC-based control.
System examples include:

- Ethernet systems using SoftPAC, a software-based programmable automation controller programmed with PAC Control
- Ethernet systems using the OptoMMP protocol
- Direct control of I/O using no I/O processor (no brain)
- Serial control using a brain and the mistic or Optomux protocol
- High-speed control using the Pamux protocol

This guide provides instructions on how to set up EtherNet/IP messaging between an Allen-Bradley® Logix™ controller and Opto 22’s SNAP PAC I/O using Opto 22’s EtherNet/IP Configurator as well as Allen-Bradley’s RSLogix™ 5000 software.

This document shows you how to set up communication between Ethernet-based Modbus systems (using Modbus/TCP) and the SNAP PAC System. In addition to the SNAP PAC System (SNAP PAC S-series and R-series controllers and SNAP PAC brains), the guide also covers Modbus/TCP communication with older Opto 22 Ethernet-based devices, including SNAP Ethernet, SNAP Simple, and SNAP Ultimate I/O; and E1 and E2 brain boards.

This white paper explores the use of intelligent remote I/O in industrial automation systems. Employing a distributed architecture, rather than centralized control, offers three advantages: minimizing single points of failure, spreading the load, and maximizing scalability.

The paper details applications that could be made more efficient by using built-in functions offered by intelligent remote I/O. It also gives a specific example of how distributed intelligence could be used in a PLC system.

This white paper discusses the strengths of traditional programmable logic controller (PLC) systems and distributed control systems (DCSs). The paper weighs methods of adding process control to a PLC-based system and proposes distributed I/O processing as the best method. It also introduces intelligent remote SNAP I/O, which adds process control analog functions.

NASA’s Deep Space Network site in Madrid experienced a crisis when engineers detected cracks in the elevation bearings of a 230-foot parabolic antenna that enables 24/7 monitoring of satellites, space probes, and spacecrafts. These bearings support the 4 million pound weight of the antenna as it tilts up and down.
To determine the precise nature of the problem, the antenna's bearings will be lifted and the existing shim pack removed and replaced with load cell transducers, which will convert the measured pressured into an electrical signal output and deliver it to an Opto 22 SNAP PAC System. Specifically, SNAP-AIMA analog input modules will connect four
sets of load cells (one for each set of bearings) to SNAP-PAC-EB2 brains, which will receive accurate load cell readings as the antenna moves across the bearings. NASA’s Jet Propulsion Laboratory will then be studying the data, formulating theories, and determining why the antenna’s bearings have been cracking.

This technical note introduces the Modbus protocol and gives you basic information for using it to communicate between Opto 22 products and other devices. Because Modbus and Modbus/TCP are handled differently by various manufacturers, the tech note describes specific areas that may be a concern and includes troubleshooting suggestions.

This CAD file contains a 3-dimensional drawing of the SNAP-PAC-EB2 Ethernet brain, which provides I/O processing and communications. This drawing also applies to the SNAP-PAC-EB2-FM, which is Factory Mutual approved.